Since the Velvet revolution of 1989, weakening of the role and position of the preparatory proceedings has been a significant and recurrent motive in the ongoing reform of the Czech law of criminal procedure. This contribution strives to provide a legal analysis of the possibilities of the said weakening with regard to the overall conception of the criminal procedure. The current conception of Czech criminal procedure is still based on so-called reformed (or mixed) inquisitive model, whose characteristic leading trait is an effort to find the material truth and to secure all of the possible pieces of evidence before deciding to bring the case to a judicial trial. Every attempt to weaken the legal capacities of the bodies of preparatory proceedings to find, secure and assess evidence must therefore be considered with respect to this principle, which raises a question of how to ideally balance the obligation of the bodies of criminal proceedings to pursue material truth with the desired diminishing of the importance and corresponding length of the preparatory proceeding. This contribution creates schematics of the possible solutions and tries to explain the pitfalls of the said balancing.